Hagel J. (2005). Only Sustainable Edge. Harvard Business.
Lua i Stíl Chicago (17ú heag.)Hagel J. Only Sustainable Edge. Boston: Harvard Business, 2005.
Lua MLA (9ú heag.)Hagel J. Only Sustainable Edge. Harvard Business, 2005.
Rabhadh: Seans nach mbeach na luanna seo go hiomlán cruinn i ngach uile chás.